Piston ring



Oct. 22, 1929. T. o. MLENDoN ETAL 1,732,978

PISTON RING Filed June lll 1927 I BY ab. /Rv//vs ATTORNEY Patented @et 22, 1929 STATES maar assisi;

THOMAS 0. MCLENLDOI AND JAMES H. R'VNG, OF VALDSTA, GEORGEA IPSTON RING Application filed June 11,

This invention relates to a piston intended especially for use in internal combustion engines, but which may permissibly be applied to steam engines. 'if he object of the invention 5 is to provide a piston adapted to lit a wide range of cylinder diameters and which will automatically compensate for wear of the cylinder into which it is fitted.

Ref r ling now to the drawings,

o Figure l shows a side elevation in vertical section of a piston embodying our invention.

IFigure shows a horizontal cross section of the piston talren on the line 2 2 of Figure l, with parts broken away.

Figure 3 shows a horizontal cross section of a piston embodying another form of our invention. This view is taken on a line corresponding to 2 2 of Figure l.

lligure l is a perspective view of a presser pin used in the embodiment shown in F igi5 Referring again to Figures l and 2, nu-

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neral l indicates the wall of the engine cylinder while 2 is the body or shell of the piston. 8 indicates the customary wrist pm and d the crank. rlhe piston shell has also the cusbring shown at 5. lt is to be understood that any suitable number of grooves and rings therefor may be used. The piston rings themselves are indicated by numerals 6. These are not ordinary rings, since they have their top inside edges beveled off, but in other resp -ets they are no differentfrom the customary rings.

Through the piston shell, there ar-e a number of holes (four in the construction shown in lligure l) drilled in each groove 5, in the lr rer portion of same. The holes are for the accommodation of an equal number of presser pins 7, which extend through them. The outer ends of the pins are partially beveled l partially straight as shown, so that they l the beveled i ier side of the piston L i; and exert a certain downward and outward pressure on the said rings. Owing to the fact that the pins 7 are pressed outward 192'?. Serial No. 193,122.

by springs 8, good contact is maintained between the cylinder walls and the piston rings, so that the escape of gas or oil past the rings is substantially prevented.

T he retaining means for the springs 8 and 5; pins 7 is a spider7 consisting substantially of four tubes or shells 9, open at their outer ends and closed as to their inner ends. The inner ends of each two shells are joined'together by means of flat tangs. The construction may be that of a tube flattened in its middle portion. lwo such flattened tubes are crossed at right angles so that the flat portions overlie cach ther. rlChey are then adjustably fastened together by means of a bolt and bolt hole drilled through both tubes. The springs and presser pins are then inserted'. rEhe ent-ire assembled device is then slipped into the piston shell. before the wrist pin has been placed therein. The presser pins are allowed to come through the openings in the shell already provided for them and so against the inner piston ring surfaces. The piston is then inserted in the cylinder.

ln the modification shown in Figure 3, the number of presser pins is increased from four to eight. Since it would be mechanically very diilicult if not impossible to provide a satisfactory spider of this description with eight legs, the spider in this case is made with only four, as before, but each lleg has fastened to it a quadrant l0 of sheet metal. To one end of the quadrant is bolted a spring clip ll, also of sheet metal. Figure 3 shows the shape of this clip clearly and also the U shaped m8 notch lla therein near its end.

As will be seen from Figure 3, the clip stands out from the quadrant l() considerably, the distance between the notch ll and the wall of the cylinder being such that it is just ,99 suliicient to accommodate the length of presser pin l2 (shown in Figures 3 and l). It will of course be evident that additional holes are drilled into piston shell to accommodate the added presser pins. rll`he latter are provided near their inner ends with a deep groove 12a extending completely around their circumferences. rlhe shank thus formed is adapted to lit the notch 11EL tightly, so that when l2 and ll are assembled together as shown in Figure 3, approximately the same pressure will be produced on the added four pins as on the four original ones. By the use of the auxiliary pins, a more even pressure on the piston ring may be maintained.

It will be readily understood by those skilled in the art that the pressing devices may be superposed as shown in Figure l of the drawings and also that as many of them may be used in one piston as is desirable. Other modifications may be made Without departing from the spirit of our invention and all such modiiieations we claim as our own if they fairly fall within the scope of the appended claims.

We claim:

1. In combination, a hollow piston body, a plurality of grooves around the circumfen ence of said body, a gas check ring in each groove, said rings being beveled as to their top inner edges and a plurality ot pins extending through said piston body, the outer ends of the said pins fitting the inner edges of the said rings and spring means within the piston adapted to exert a steady outward pressure on the pins and rings, said spring means being retained in a pair ot crossed tubular members flattened as to their middle portions and bolted together through said flattened middle portions and adapted to house the spring means.

2. In combination, a hollow piston body, a plurality of grooves around the circumference of said body, a gas check ring in each groove, said rings being beveled as to their top inner edges and a plurality oi pins eX- tending through said piston body, the outer ends of the said pins fitting' the inner edges of the said rings and spring means within the piston adapted to exert a steady outward pressure on the pins and rings, a pair ot crossed tubular members iiattened as to their middle portions and bolted together through said flattened middle portions, said spring means being retained in the tubular members and auxiliary spring pressing means comprising sheet metal quadrants attached to each oft said of the tubular members, spring clips fastened to said quadrants and extending outwardly therefrom, said clips having U shaped notches therein near their outer ends, presser pins within the notches` the said pins being adapted to engage the inner sides of the piston rings and press them outwardly.

3. A device for increasing the obtrratina,` qualities oit piston rings comprising a plural; ity of hollow tubular shells closed at one end, flat Shanks on the closed ends of the shells joining the shells together in pairs end to end. the Shanks of a plurality of the ioined shells being superposed upon each otherand bolted together, the shells containing each a coil spring and a pin beveled at its outer end.

4. device for increasing the obturating qualities of piston rings comprising a plurality of hollow tubular shells closed at one end, flat shanlrs on the closed ends of the shells joining the shells together in pairs end to end, the Shanks of a plurality of the joined shells being superposed upon each other and bolted together, the shells containing each a coil spring and a pin beveled at its outer end, and a plurality ot'auxiliary pressing pins, said pins being retained in spring clips fastened to sheet metal quadrants extending between the main presser pin holding members and being fastened thereto.

A. device -tor increasing the obturating qualities of piston rings comprising a plurality of hollow tubular shells closed at one end, Shanks on the closed ends of the shells ioinin the shells together in pairs end to end, each shell. containing a coil spring and a pin forced outwardly from the shell by the spring, the outer free end of the pin being provided with a. shoulder, and a bevelled edge to engage the inner tace of a ring.

THOMAS 0; MGLENDON. JMES H. IRVING. 

